PROCESS OF MAKING ClF{11 O

ABSTRACT

Production of CIF3O by reacting under ultraviolet light a compound selected from the group consisting of ClF2F and ClO3F with a compound selected from the group consisting of ClF5, ClF3, ClF, OF2 and F2.

0 WWWfl Slales PMNW 1 [111 3,718,557 Rogers et al. 1 Feb. 27, 1973 1PROCESS OF'MAKING CLF O v [56] References Cited [75] Inventors: HowardH. Rogers, Woodland Hills; UNITED STATES PATENTS Donald Pilipovich,Canoga Park, both f C |if 3,285,842 1l/l966 Grosse et al ..204/157.1

[73] Assignee: North American Rockwell Corporaon Primary ExammerReubenEpstein Attorney-William R. Lane, Thomas S. MacDonald [22] Flled: 1967and Richard L. Mikesell. [21] App]. N0.: 688,628

[57] ABSTRACT [52] lU.S.Cl ..204/157.l, 23/203 Production of CIFaO byreacting under ultraviolet 51 1m. (:1. ..B0lj 1/00 light a compoundSelected from the group consisting v of CIF F and ClO F with a compoundselected from [58] Field of Search "204/1571; 23/203 the groupconsisting of ClF ClF ClF, 0F and F 4 Claims, N0 Drawings PROCESS OFMAKING ClF3O The Invention herein described was made in the course of orunder a contract with the Department of the Navy.

REFERENCES TO RELATED APPLICATIONS This invention is related toco-pending application Ser. No. 543,493 filed Apr. 13, 1966, in thenames of D. Pilipovich, R. D. Wilson, and H. F. Bauer, having a commonassignee.

BACKGROUND OF THE INVENTION In the constant search for high energyliquid rocket oxidizers, fluorine and its energetic compounds has beenthe object of much investigation.

PRIOR ART Co-pending application, Ser. No. 543,493, describes and claimsa new fluorine oxidizer, oxychlorine trifluoride (CIF O), and a methodfor its manufacture. The compound ClF O is attractive as an oxidizer,particularly for use in rocket engines. Its advantages include low bondenergies and relatively good storability. However, the method ofsynthesis in that case, although satisfactory for laboratory production,may not be as economical as might be desired for large scale production.

It is an object of this invention to provide an improved process for thesynthesis of ClF O.

Other and more specific advantages of this invention will becomeapparent from the following description:

SUMMARY OF THE INVENTION UV Y X ClF O side products where X is acompound selected from the group consisting of ClF ClF ClF, OF, and Fand Y is CIO,F or ClO F. The uv represents the input of ultravioletenergy. The reactants should preferably be present in nearstoichiometric ratios. Of course, much smaller or larger ratios will notpreclude the reaction of the instant invention, but percent yields willbe small when less than the stoichiometric amount of fluorine is used.

The reaction of the instant invention should take place at reducedtemperatures. Generally, temperatures of between -80 and +lC areconsidered to be suitable. However, temperatures of between -60C and-40C are preferred. The reaction mixture is preferably at autogeneticpressure. The reaction should take place in a highly resistant containersuch as stainless steel, nickel, or Monel, due to the corrosive natureof the reactants. Although some reaction takes place immediately, it isusually preferred to irradiate from A to 3 hours.

As is known to those skilled in the art, the radiant energy imparted bya source is proportional to the wave length of that radiant energy.However, if radiant energy is to promote a reaction, it must be of awave length that can be absorbed by one or more of the reactants. It isthese criteria that must be kept in mind if a narrow spectrum ofultraviolet light is used in the reaction of the instant invention. Inpractice a wide spectrum ultraviolet source, for instance, a mercuryvapor lamp,

has been found to be satisfactory in the syntheses of the instantinvention. The absorbance of this reaction was investigated betweenabout 1,900 and about 3,100 angstroms. Above about 3,100 angstroms therecited compounds do not appreciably absorb light. Below about 1,900angstroms a vacuum or He-filled uv apparatus must be used as atmosphericoxygen begins to absorb ultraviolet radiation at about that point. In anapparatus using a sapphire window ultraviolet emissions down to about1,650 angstroms can be used. In an apparatus using a lithium fluoridewindow radiations down to about 1,200 angstroms can be used. Bothsapphire and lithium fluoride are resistant to the reactants andproducts of the instant invention. Such low wave lengths are somewhatuncommon although their use is contemplated within the scope of theinvention.

It has been found that the compound ClF has a maximum point ofabsorbance at a wave length of about 2,730 angstroms. The compound C11on the other hand, appears not to have a maximum but rather a steadilyincreasing absorbance coefficient towards shorter wave lengths.Similarly, the compound OF, has a steadily increasing absorbancecoefficient towards shorter wave lengths. However, the compound ClF: hasa maximum absorbance of between 2,000 and 2,100 angstroms, and fluorinehas a maximum absorbance at about 2,845 angstroms.

After reaction, the resultant ClF O can be separated from any sideproducts by conventional means. Fractional condensation has been foundto be satisfactory. ClF O freezes at about 37C.

While the reaction was run experimentally in a batch type process, itcan be readily performed in a flow operation. In this type of operation,the reactants in the gaseous state would be mixed, radiated and thenpassed into a cold zone for condensation and separation of the desiredproduct.

The reaction of the instant invention is illustrated by the followingtypical syntheses in which a 100 w. utility mercury vapor lamp wasplaced one-eighth inch from a sapphire window in a cooled nickel batchreactor:

TABLE I Ultraviolet Activated Reactions Mole Ratio Temp Time,Condensible Products, Reactants (to 1) C hr Mole Percent (Conversion)(a) F,,FCIO, 12.8 -60 5.4 ClF,O, 14; C11 59 F,,FC10, 5.6 60 2.5 ClF,O,5.0; Clfi, 26 F,,FC10, 1.1 60 4.2 ClF,O, 36; CIF 8; ClF,, 22; FC10,, 6OF,,FC10, 1.0 60 4.1 C1F,O, 20; ClF,, 17; GP, 57 CIFFCIO, 2.0 60 4.1ClF,0, 26; C11 C1, C1F,,FC10, 1.0 60 4.1 C1F,0, 28; ClF ClF,,, FCIO, 1.060 4.0 ClF,O, ClF, ClF., FClO, 1.0 -60 3 CIF,O, 63; ClF,; ClF, 15ClF,,FClO, 1.0 40 1 ClF,0, 63.2; FClO 29.7 F,,FC10, 1.0 60 1 C1F,0, 30

(a) All products were determined quantitatively but values are listedonly if origin of product was only from compound being fluorinated.

Since it is obvious that many changes and modificasecond compoundselected from the group consisttions can be made in the above describeddetails ing of ClF ClF ClF, P and F thereby without departing from thenature and spirit of the incausing reaction, forming ClF O andsubsequently vention, it is to be understood that the invention is notSeparating said ClF O. to be limited thereto except as set forth in theap- 5 The Process of Claim 1 wherein the miXtUre 0f pended claims,reactants is at between -60C and 40C.

We claim: 3. The process of claim 1 wherein the first compound 1. Theprocess of making ClF O comprising i5 z irradiating with ultravioletlight a mixture at between The Process of clam 2 wherein the firstcompound -80C +C of a first compound selected from CIOZF- the groupconsisting of ClO F and ClO F and a

2. The process of claim 1 wherein the mixture of reactants is at between-60*C and -40*C.
 3. The process of claim 1 wherein the first compound isClO2F.
 4. The process of claim 2 wherein the first compound is ClO2F.